1. Field of the Invention
The present invention relates to a resin composition for sealing a semiconductor device and a semiconductor device sealed with the resin composition.
2. Description of the Prior Art
When a semiconductor device is sealed with plastics under the recent trend of high integration and large-sizing of the semiconductor devices, there is a problem that the semiconductor device is reduced in its reliability, such as breakage of bonding lines and cracks in the device, due to thermal stress caused by the difference of thermal expansion coefficients between the device or a lead frame and the sealing resin compositions. As a base material for reducing the thermal stress, a compounding method utilizing 1,4-polybutadiene rubber having at least one of carboxyl group, hydroxyl group and epoxy group is already known. (Japanese Patent Publication No. Sho 63-51447)
The resin composition by the method using 1,4-polybutadiene, however, is poor in heat resisting property, such as it is oxidized at the high temperature.